Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Our Management’s Discussion and Analysis of Financial Condition and Results of Operations includes the following sections:

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Overview that discusses our business.

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Results of Operations that includes a discussion of our revenue and expenses.

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Liquidity and Capital Resources that discusses key aspects of our statements of cash flows, changes in our financial position and our financial commitments.

Overview

Plus Therapeutics is a U.S. pharmaceutical company developing targeted radiotherapeutics with advanced platform technologies for central nervous system (“CNS”) cancers. Our novel radioactive drug formulations and medical devices and therapeutic candidates are designed to deliver safe and effective doses of radiation to tumors. To achieve this, we have developed innovative approaches to drug formulation, including encapsulating radionuclides such as rhenium isotopes with nanoliposomes and microspheres. Our formulations are intended to achieve elevated patient-absorbed radiation doses and extend retention times such that the clearance of the isotope occurs after significant and essentially complete radiation decay, which will contribute and provide less normal tissue/organ exposure and improved safety margins.

Traditional approaches to radiation therapy for cancer, such as external beam radiation, have many disadvantages including continuous treatment for four to six weeks (which is onerous for patients), that the radiation damages healthy cells and tissue, and that the amount of radiation delivered is very limited and, therefore, is frequently inadequate to fully destroy the cancer.

Our targeted radiotherapeutic platform and unique investigational drugs have the potential to overcome these disadvantages by directing higher, more powerful radiation doses at the tumor—and only the tumor—potentially in a single treatment. By minimizing radiation exposure to healthy tissues while simultaneously maximizing locoregional delivery and, thereby, efficacy, we hope to reduce the radiation toxicity for patients, improving their quality of life and life expectancy. Our radiotherapeutic platform, combined with advances in surgery, nuclear medicine, interventional radiology, and radiation oncology, affords us the opportunity to target a broad variety of cancer types.

Our lead radiotherapeutic candidate, REYOBIQTM (rhenium (186Re) obisbemeda), is designed specifically for CNS cancers including recurrent glioblastoma (“GBM”), leptomeningeal metastases (“LM”), and pediatric brain cancers (“PBC”) by direct localized delivery utilizing approved standard-of-care tissue access such as with convection-enhanced delivery (“CED”) and intraventricular brain (Ommaya reservoir) catheters. Our acquired radiotherapeutic candidate, Rhenium-188 NanoLiposome Biodegradable Alginate Microsphere (“188RNL-BAM”), is designed to treat many solid organ cancers including primary and secondary liver cancers by intra-arterial injection.

On April 26, 2024, we acquired all of the right, title and interest in a cerebrospinal fluid cancer diagnostic portfolio known as the CNSide® Platform from Biocept, Inc. (“Biocept”), which is currently being utilized in the ReSPECT-LM clinical trial funded by the Cancer Prevention and Research Institute of Texas (“CPRIT”). In connection with our business plan for developing the CNSideTM Platform, we formed CNSide Diagnostics, LLC (“CNSide Diagnostics”), a wholly owned subsidiary of the Company, and our board of directors appointed a board of managers for CNSide Diagnostics. We are planning for the CNSide Cerebrospinal Fluid Tumor Cell Enumeration test (the “CNSideTM Test”), which is a laboratory developed test (“LDT”), to be re-introduced to the U.S. market starting in the second quarter of 2025 after we complete a number of steps related to certifications, state licensure, payor coverages, reimbursement codes and financing.

In March 2025, we moved our headquarters to Houston, Texas, in proximity to world-class cancer institutions and researchers.

Pipeline

Our most advanced investigational drug, REYOBIQTM, is a patented radiotherapy potentially useful for patients with CNS and other cancers. We announced in March 2025 that the U.S. Food and Drug Administration (“FDA”) conditionally accepted the proprietary name REYOBIQTM to be used by us for rhenium (186Re) obisbemeda. Preclinical study data describing the use of REYOBIQTM for several cancer targets have been published in peer-reviewed journals and reported at a variety of medical society peer-reviewed meetings. Besides GBM, LM and PBC, REYOBIQTM has been reported to have potential applications for head and neck cancer, ovarian cancer, breast cancer and peritoneal metastases.

The REYOBIQTM technology was part of a licensed radiotherapeutic portfolio that we acquired from NanoTx, Corp. (“NanoTx”) on May 7, 2020. The licensed radiotherapeutic has been evaluated in preclinical studies for several cancer targets and we have an active $3.0 million award from U.S. National Institutes of Health/National Cancer Institute which is expected to provide financial support for

the continued clinical development of REYOBIQTM for recurrent GBM through the completion of a Phase 2 clinical trial, including enrollment of up to 55 patients.

On August 29, 2022, we announced feedback from a Type C meeting with the FDA regarding Chemistry, Manufacturing and Controls practices.

The FDA indicated agreement with our proposed application of cGMP guidance for radiotherapeutics, small molecule drug products and liposome drug products for REYOBIQTM in support of ongoing and future GBM clinical trials, manufacturing scale up, and commercialization. Alignment with the FDA includes support of our proposed controls and release strategy for new drug substance and new drug product. Because this product is identical for recurrent GBM, LM, and PBC, we believe alignment will be consistent for REYOBIQTM used in other clinical development programs, including LM and PBC.

REYOBIQTM versus External Beam Radiation Therapy for Recurrent GBM

REYOBIQTM is a novel injectable radiotherapy designed to deliver targeted, high dose radiation directly into GBM tumors in a safe, effective, and convenient manner that may ultimately prolong patient survival. REYOBIQTM is composed of the radionuclide Rhenium-186 and a nanoliposomal carrier, and is infused in a highly targeted, controlled fashion, directly into the tumor via precision brain mapping and CED catheters. Potential benefits of REYOBIQTM compared to standard external beam radiotherapy or external beam radiation therapy (“EBRT”) include:

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The REYOBIQTM radiation dose delivered to patients may be up to 20 times greater than what is possible with commonly used EBRT, which, unlike EBRT and proton beam devices, spares normal tissue and the brain from radiation exposure.

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REYOBIQTM can be visualized in real-time during administration, possibly giving clinicians better control of radiation dosing, distribution and retention.

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REYOBIQTM potentially more effectively treats a bulk tumor and microscopic disease that has already invaded healthy tissue.

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REYOBIQTM is infused directly into the targeted tumor by CED catheter insertion using MRI guided software to avoid critical patient neurological structures and neural pathways and also bypasses the blood brain barrier, which delivers the therapeutic product where it is needed. Importantly, it reduces radiation exposure to healthy cells, in contrast to EBRT, which passes through normal tissue to reach the tumor, continuing its path through the tumor, hence being less targeted and selective.

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REYOBIQTM is given during a single, short, in-patient hospital visit, and is available in all hospitals with nuclear medicine and neurosurgery, while EBRT requires out-patient visits five days a week for approximately four to six weeks.

ReSPECT-GBM Trial for Recurrent GBM

GBM affects approximately 15,000 patients annually in the U.S. and is the most common and lethal form of brain cancer. The average life expectancy with GBM is less than 24 months, with a one-year survival rate of 40% and a five-year survival rate of around 5%. There is no clear standard of care for recurrent GBM and the few currently approved treatments provide only marginal survival benefit and are associated with significant side effects, which limit dosing and prolonged use. Approximately 90% of patients experience GBM tumor recurrence at or near the original tumor location, yet there are no FDA-approved treatments in the recurrent or progressive setting that can significantly extend a patient’s life. GBM routinely presents with headaches, seizures, vision changes and other significant neurological complications, with a significant compromise in quality of life. Despite the best available medical treatments, the disease remains incurable. Even after efforts to manage the presenting signs and symptoms and completely resect the initial brain tumor, some microscopic disease almost always remains and tumor regrowth occurs within months. Complete surgical removal of GBM is usually not possible and GBM is often resistant or quickly develops resistance to most available current and investigational therapies. Today, the treatment of GBM remains a significant challenge and it has been nearly a decade since the FDA approved a new therapy for this disease, and these more recent approvals have not improved the overall survival (“OS”) for GBM patients over past decades, and a significant unmet medical need persists.

While EBRT has been shown to be safe and has temporary efficacy in many malignancies including GBM, typically at absorbed, fractionated radiation dose of ~30 Gray in GBM, this maximum possible administered dose is always limited by toxicity to the normal tissues surrounding the malignancy and because EBRT requires fractionation to manage toxicity and maximum EBRT limits are typically reached before long-term efficacy reached. Because of this limitation, EBRT cannot provide a cure or long-term control of GBM and GBM always recurs within months after EBRT. In contrast, locally delivered and targeted radiopharmaceuticals that precisely deliver radiation in the form of beta particles such as Iodine-131 for thyroid cancer, are known to be safe and effective and minimize exposure to normal cells and tissues especially with optimal administered dose and minimizing exposure to normal tissue. The locally delivered REYOBIQTM is designed for and provides patient tolerability and safety. Though no REYOBIQTM head-to-head trial with

chemo, immune, EBRT or systemic radiopharmaceutical products have been conducted, patient tolerability and safety considerations have been reported as expected.

In September 2020, the FDA granted both orphan drug designation and Fast Track designations to REYOBIQTM for the treatment of patients with GBM.

REYOBIQTM is under clinical investigation in a Phase 1/2 multicenter, sequential cohort, open-label, volume and dose escalation study (“ReSPECT-GBM”) of the safety, tolerability, and distribution of REYOBIQTM given by CED catheters to patients with recurrent or progressive malignant glioma after standard surgical, radiation, and/or chemotherapy treatment. The trial is funded through Phase 2 in large part by a National Institute of Health/National Cancer Institute grant.

On January 18, 2023, we announced that the first patient was dosed in Phase 2 of the ReSPECT-GBM Phase 1/2 trial evaluating REYOBIQTM for the treatment of recurrent GBM. Phase 2 of the trial is expected to enroll up to 34 total patients with small- to medium-sized tumors and is targeted for full enrollment by the end of 2025. We currently have four clinical sites, and expect a data read-out by the end of 2025.

On September 30, 2024, we showcased new interim ReSPECT-GBM Phase 2 Trial Data at the 2024 Congress of Neurological Surgeons Annual Meeting that included the following findings as of that date:

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42 total patients enrolled in ReSPECT-GBM trial at 3 sites, with 19 out of 42 patients having been treated at the recommended Phase 2 dose (22.3 mCi in 8.8 mL) in tumors of approximately 20 cm3 or less.

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All Phase 2 patients have recurrent, histologically confirmed glioblastoma; 1 recurrence, bevacizumab naïve, single tumor of approximately 20 cm3 or less (small-to-medium sized tumors).

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Average tumor size in Phase 2 was 7.5 mL (range 0.9-22.8 mL).

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Increases in absorbed dose correlated with specific drug delivery parameters such as infused dose and volume, maximal convection flow rate, and number of catheters.

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REYOBIQTM continues to show a favorable safety profile in the 42 enrolled patients; one dose-limiting toxicity (hemiplegia) has been reported, which was observed in Cohort 8 (41.5 mCi and 16.3 mL).

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In Phase 2, most adverse events were mild (73.5%) or moderate (18.8%), and largely unrelated (37.7%), or unlikely related (27.1%) to the drug. Of the 9 severe adverse events, only 2 were related to the study drug.

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Average absorbed radiation dose to the tumor in Phase 2 was 300 Gy (n=18, 1 patient still under analysis).

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88.9% of Phase 2 patients met key CED drug delivery parameters shown to correlate with overall survival, achieving a tumor absorbed dose >100 Gy and radiation coverage of >70%.

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29 out of 42 patients treated thus far participated in the Phase 1 dose escalation phase of the trial (as per protocol, 6 out of 42 patients were included in both the Phase 1 and Phase 2 trial arms and related analyses).

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Phase 1 dose-escalation increased administered doses from 1.0 mCi to 41.5 mCi and volumes from 0.66 mL to 16.3 mL.

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In terms of objective tumor response based on quantitative image analysis, a statistically significant reduction in tumor volume rate change was seen in tumors receiving > 100 Gy absorbed dose (n=11 patients analyzed to date, p<0.005). Sufficient tumor coverage correlated with tumor control, while regrowth occurred outside treated areas.

We completed Phase 1 of our ReSPECT-GBM Trial and are targeting full enrollment into Phase 2 by the end of 2025.

ReSPECT-LM Clinical Trials for LM

LM is a rare complication of cancer in which the disease spreads to the membranes (meninges) surrounding the brain and spinal cord. The incidence of LM is growing and occurs in approximately 5%, or more, of people with late-stage cancer, or 110,000 people in the U.S. each year. It is highly lethal with an average one-year survival of just 7%. All solid cancers, particularly breast, lung, GI, and melanoma, have the potential to spread to the leptomeninges.

The ReSPECT-LM Phase 1 clinical trial (ClinicalTrials.gov NCT05034497) was preceded with preclinical studies in which tolerance to doses of REYOBIQTM as high as 1,075 Gy were shown in animal models with LM without significant observed toxicity. Furthermore, treatment led to a marked reduction in tumor burden in both C6 and MDA-231 LM models.

Upon receiving acceptance of our Investigational New Drug application and Fast Track designation by the FDA for REYOBIQTM for the treatment of LM in November 2021, we initiated the trial and began screening patients for the ReSPECT-LM Phase 1 clinical trial in the fourth quarter of 2021.

ReSPECT-LM is a multi-center, sequential cohort, open-label, dose escalation study evaluating the safety, tolerability, and efficacy of a single-dose application of REYOBIQTM administered through intrathecal infusion to the ventricle of patients with LM after standard surgical, radiation, and/or chemotherapy treatment. The primary endpoint of the study is the incidence and severity of adverse events and dose limiting toxicities, together with determining the maximum tolerated and recommended Phase 2 dose. Full enrollment in the Phase 1 trial was achieved at the end of 2024, and we announced the trial completion on February 26, 2025. Trial closeout procedures are now taking place including final data review and monitoring, and a clinical study report and manuscript will be prepared.

On September 19, 2022, we entered into a Cancer Research Grant Contract (the “CPRIT Contract”), effective as of August 31, 2022, with CPRIT, pursuant to which CPRIT provides us a grant of up to $17.6 million (the “CPRIT Grant”) over a three-year period to fund the continued development of REYOBIQTM for the treatment of patients with LM through Phase 2 of the ReSPECT-LM clinical trial. The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar from us for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of REYOBIQTM based on specific dollar thresholds until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements. As of December 31, 2024, we had received approximately $10.4 million in milestone payments under the CPRIT Contract.

Interim results showed that a single treatment with REYOBIQTM resulted in a consistent decreased cerebrospinal fluid (“CSF”) tumor cell count/ml and was tolerated by all LM patients. REYOBIQTM is an outpatient administration and treatment and is easily and safely administered through a standard intraventricular catheter (Ommaya Reservoir), distributed promptly throughout the CSF, and with durable retention in the leptomeninges at least through day seven. All patients have shown well tolerated prompt and durable REYOBIQTM distribution throughout the subarachnoid space.

In November 2023, the FDA granted orphan drug designation to REYOBIQTM for the treatment of patients with breast cancer with LM.

On December 12, 2023, we announced our partnership with K2bio to implement novel analysis for CSF tumor and molecular biomarkers for CNS cancers.

On February 26, 2025, we announced the completion of the ReSPECT-LM Phase 1 single-dose escalation trial, having determined a recommended Phase 2 dose. Enrollment in Cohort 6 was completed (75.0 mCi). The Cohort 4 dose (44.1 mCi) was determined to be the recommended Phase 2 dose with no dose-limiting toxicities observed at that dose level. One patient at the Cohort 4 dose was observed to have achieved a complete response, as evidenced by the eradication of tumor cells in the cerebrospinal fluid—a key therapeutic endpoint.

We anticipate beginning enrollment for a ReSPECT-LM Multi-Dose trial in the first half of 2025. In March 2025, the FDA granted orphan drug designation to REYOBIQTM for the treatment of LM in patients with lung cancer.

ReSPECT-PBC Clinical Trial for Pediatric Brain Cancer

The average annual age adjusted mortality rate for children aged 0-14 for malignant brain (and other CNS) tumors is 0.71/100,000, making it the most common cause of death and cancer death in this age group. The 2021 World Health Organization Classification of CNS Tumors classifies gliomas, glioneuronal tumors, and neuronal tumors into six different families: (1) adult-type diffuse gliomas; (2) pediatric-type diffuse low-grade gliomas; (3) pediatric-type diffuse high-grade gliomas (“HGG”); (4) circumscribed astrocytic gliomas; (5) glioneuronal and neuronal tumors; and (6) ependymomas.

In August 2021, we announced plans for treating pediatric brain cancer at the 2021 American Association of Neurological Surgeons Annual Scientific Meeting. In July 2021, we reported that we had received FDA feedback pertaining to a pre-Investigational New Drug Application (“IND”) meeting briefing package in which the FDA stated that we are not required to perform any additional preclinical or toxicology studies.

Given the initial FDA feedback, receipt of adult GBM data and experience with REYOBIQTM and follow-up communications with the FDA, we submitted a pediatric brain tumor IND for our ReSPECT-PBC clinical trial to investigate the use of REYOBIQTM in two pediatric brain cancers, high-grade glioma and ependymoma, in the fourth quarter of 2024.

Pediatric high-grade gliomas can be found almost anywhere within the CNS; however, they are most commonly found within the supratentorium. The highest incidence of supratentorial, high-grade gliomas in pediatrics appears to occur in children aged 15 to 19

years, with a median age of approximately nine years. Overall, pediatric high-grade glioma confers a three-year progression free survival (“PFS”) of 11 ± 3% and three-year OS of 22 ±5%. One-year PFS is as low as 40% in recent trials. Ependymomas are slow-growing central nervous system tumors that involve the ventricular system. Diagnosis is based on MRI and biopsy and survival rate depends on tumor grade and how much of the tumor can be removed. Grade II pathology was associated with significantly improved OS compared to Grade III (anaplastic) pathology (five-year OS = 71 ± 5% vs. 57 ± 10%; p = 0.026). Gross total resection compared to subtotal resection was associated with significantly improved OS (five-year OS = 75 ± 5% vs. 54 ± 8%; p = 0.002).

Overall, pediatric HGG and ependymoma are extremely difficult-to-treat pediatric brain tumors, frequently aggressive, and in recurrent settings, carry an extremely poor prognosis.

Effective September 1, 2024, we entered into an agreement with the Department of Defense office of the Congressionally Directed Medical Research Programs to receive a $3.0 million fund for research and development purposes (“DoD Award”) over a three-year period. The DoD Award will be used to support the planned expansion of our clinical trial for pediatric brain cancer. We anticipate beginning enrollment for our Phase 1 ReSPECT-PBC clinical trial in 2025.

Rhenium-188 NanoLiposome Biodegradable Alginate Microsphere Technology

In January 2022, we announced that we licensed Biodegradable Alginate Microsphere (“BAM”) patents and technology from The University of Texas Health Science Center at San Antonio (“UTHSCSA”) to expand our tumor targeting capabilities and precision radiotherapeutics pipeline. We intend to combine our Rhenium NanoLiposome technology with the BAM technology to create a novel radioembolization technology. Initially, we intend to utilize the Rhenium-188 isotope, 188RNL-BAM for the intra-arterial embolization and local delivery of a high dose of targeted radiation for a variety of solid organ cancers such as hepatocellular cancer, hepatic metastases, pancreatic cancer and many others.

Preclinical data from an ex vivo embolization experiment in which Technetium99m-BAM was intra-arterially delivered to a bovine kidney perfusion model was presented at the Society of Interventional Radiology Annual Scientific Meeting. The study concluded that the technology required for radiolabeling BAM could successfully deliver, embolize and retain radiation in the target organ. 188RNL-BAM is a preclinical investigational device we intend to further develop and move into clinical trials. Specifically, in 2022 we transferred the 188RNL-BAM technology from UTHSCSA, and began planning to develop the product and complete early preclinical studies to support a future FDA IND submission. Our intended initial clinical target is liver cancer which is the sixth most common and third deadliest cancer worldwide. It is a rare disease with increasing U.S. annual incidence (42,000) and deaths (30,000).

The FDA has informed us that 188RNL-BAM will be regulated as a medical device under the FDCA.

The CNSideTM FORESEE Trial

The CNSideTM Platform consists of four LDTs used for treatment selection and treatment monitoring of patients with LM. The CNSideTM Platform facilitates tumor cell detection/enumeration and biomarker identification using cellular assays (immunocytochemistry (ICC) and fluorescence in situ hybridization (FISH)) and molecular assays (next-generation sequencing (NGS)). The CNSideTM Test is currently being used in the ReSPECT-LM trial as an exploratory endpoint and we are planning to re-introduce it to the US market starting in the second quarter of 2025.

In August 2024, data from the CNSideTM FORESEE clinical trial in patients with LM was presented at the Society for Neuro-Oncology (“SNO”) / American Society for Clinical Oncology (“ASCO”) CNS Metastases Conference. The trial met its key primary and secondary endpoints and the data showed that the CNSideTM Test more than doubled the diagnostic sensitivity versus gold standard cerebrospinal fluid cytology and influenced clinical management decisions in over 90% of LM cases.

On November 24, 2024, CNSide Diagnostics presented data at the 2024 SNO Annual Meeting from the FORESEE trial showcasing the CNSideTM Platform’s utility in diagnosing and guiding clinical decision making for breast cancer and non-small cell lung cancer patients with LM.

Key highlights included:

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The FORESEE trial achieved its primary endpoint, demonstrating that the CNSideTM Test influenced treatment decisions in over 90% of cases evaluated, surpassing the predetermined 20% primary endpoint target.

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The CNSideTM Test demonstrated enhanced sensitivity in detecting tumor cells (80%) vs. CSF cytology (29%) in patients with LM.

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The CNSideTM Test identified actionable mutations in the CSF, such as HER2 amplification, influencing 24% of therapeutic selection decisions.

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The CNSideTM Test exhibited high specificity, with no tumor cells detected in patients without LM.

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The CNSideTM Test demonstrated improved Negative Predictive Value in ruling out LM (25%) vs. CSF cytology (10%).

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The CNSideTM Test revealed HER2 positivity in LM tumors in 60% of breast cancer patients with HER2-negative primary tumors, informing physician treatment strategies.

Recent Developments

Recent Financings

Refer to the “Liquidity and Capital Resources” section below for information on our recent financings.

Manufacturing agreement with SpectronRX

On November 5, 2024, we entered into a manufacturing services agreement for drug product development and manufacturing (the “SpectronRx Services Agreement”) with NukeMed, Inc. d/b/a SpectronRx (“SpectronRx”), pursuant to which SpectronRx will process development and manufacturing clinical investigational pharmaceutical products to support our clinical programs. Pursuant to the SpectronRx Services Agreement, an initial proposal for drug product development and manufacturing under the SpectronRx Services Agreement is expected to become effective in the third quarter of 2025.

Under the SpectronRx Services Agreement, we will own all rights and interest in all intellectual property, including rights (i) related to copyright, patent, trademark, or other right to ideas, inventions, products, programs, procedures, process, formats, and other materials, (ii) developed solely by us in connection with developing, formulating, manufacturing, filing, processing, packaging, analyzing or testing of a (a) pharmaceutical ingredient or any intermediate thereof (“API/Drug Substance”), (b) drug product comprised of API/Drug Substance (“Drug Candidate”), or (c) intermediate(s) of (a) or (b) (together with API/Drug Substance and Drug Candidate, the “Product”), or (iii) directly related to the services rendered by SpectronRx or its subcontractors. SpectronRx will own all rights and interest in the intellectual property owned by or licensed to SpectronRx other than in connection with Products or services covered under the SpectronRx Services Agreement (the “SpectronRx Technology”). To the extent that any portion of SpectronRx Technology is required for the purpose of using or applying the Products, SpectronRx is required to provide to us a non-exclusive, royalty-free, perpetual license for that portion of SpectronRx Technology that is required by us to use and apply the Products.

Under the SpectronRx Services Agreement, upon written notice by us to SpectronRx, at least six months in advance of our first commercial manufacturing needs for a Product, SpectronRx will be required to enter into good faith negotiations with us for a commercial supply agreement governing the manufacture of such Product for commercial sale or use.

Unless earlier terminated, the SpectronRx Services Agreement will remain in place for a period of five years. Thereafter, the SpectronRx Services Agreement will automatically renew for successive one-year terms unless either party notifies the other, not later than six months in advance of the original term or any additional renewed term, of the intention to terminate it. We may terminate the SpectronRx Services Agreement (i) for any reason on prior written notice to SpectronRx, provided that we will be required to compensate SpectronRx for certain fees and costs if such cancellation is made prior to the completion of a work order, or (ii) immediately if SpectronRx files for bankruptcy, becomes insolvent, or is suspended or debarred by the FDA or the United States government. In addition, either party may terminate the SpectronRx Services Agreement within thirty days upon any material breach that is left uncured by the other party.

Department of Defense Award

Effective September 1, 2024, we entered into an agreement with the DoD office of the Congressionally Directed Medical Research Programs to receive a $3.0 million DoD Award fund for research and development purposes over a three-year period. The DoD Award will be used to support the planned expansion of our clinical trial for pediatric brain cancer. On October 4, 2024, we received the first payment under the DoD Award in the amount of $0.9 million.

Results of Operations

Grant Revenue

On September 19, 2022, we entered into the CPRIT Contract, effective as of August 31, 2022, with CPRIT, pursuant to which CPRIT will provide us a grant of up to $17.6 million (the “CPRIT Grant”) over a three-year period to fund the continued development of REYOBIQTM for the treatment of patients with LM through Phase 2 of the ReSPECT-LM clinical trial. The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, a matching fund requirement (one dollar from us for every two dollars awarded by CPRIT), revenue sharing obligations upon commercialization of REYOBIQTM based on specific dollar thresholds until CPRIT receives the aggregate amount of 400% of the proceeds awarded under the CPRIT Grant, and certain reporting requirements. Since the inception of the CPRIT Contract, we recognized $5.8 million, $4.9 million and $0.2 million of grant revenue during the years ended December 31, 2024, 2023 and 2022, respectively, of which $10.4 million has been received and $0.6 million was recorded as

grant revenue receivable as of December 31, 2024. The amounts recognized represent CPRIT’s share of the costs incurred for our REYOBIQTM development for the treatment of patients with LM.

We expect grant revenue will increase during the remaining term of the CPRIT Grant through August 2025, as we continue to expand the LM clinical trial to add clinical sites and enroll patients. In February 2025, we received $2.0 million under the CPRIT Contract. The ability to continue to access the grant remains subject to additional FDA approval of the LM clinical trial, ability to deliver expanded drug supply and continued enrollment of patients. In addition, grant revenue amounts will vary quarter to quarter based on enrollment, mandated safety periods between cohorts and required interactions with FDA.

Research and development expenses

Research and development expenses include costs associated with the design, development, testing, and enhancement of our product candidates, payment of regulatory fees, laboratory supplies, pre-clinical studies, and clinical studies.

The following table summarizes the components of our research and development expenses for the years ended December 31, 2024 and 2023 (in thousands):

Years ended December 31,

Share-based compensation 51 66

Total research and development expenses $ 10,580 $ 9,690

Research and development expenses for the year ended December 31, 2024 increased by $0.9 million as compared to the same period in 2023, primarily due to increases of approximately $0.7 million in development expenses, $0.1 million in compensation expenses, $1.1 million in professional research and development service fees, and $0.1 million in depreciation and other expenses, offset by a reduction of $1.1 million in research and development licensing expense and $0.1 million in clinical expenses.

We expect aggregate research and development expenditures to increase significantly during 2025 as compared to the corresponding comparable period ended December 31, 2024, due to increased costs for the ReSPECT-LM clinical trial (for which CPRIT grant funding is expected to be available), increases in licensing payments, offset by reduced research and development spend on the cGMP development.

General and administrative expenses

General and administrative expenses include costs for administrative personnel, legal and other professional expenses, and general corporate expenses. The following table summarizes the general and administrative expenses for the years ended December 31, 2024 and 2023 (in thousands):

Years ended December 31,

General and administrative $ 9,440 $ 8,041

Share-based compensation 499 503

Total general and administrative expenses $ 9,939 $ 8,544

General and administrative expenses increased by approximately $1.4 million during the year ended December 31, 2024, as compared to the same period in 2023. The increase was due primarily to an increase in legal and professional expenses of $1.0 million, and an increase of $0.4 million in compensation expenses.

We expect general and administrative expenditures to remain generally consistent during 2025 as compared with the corresponding comparable period ended December 31, 2024.

Share-based compensation expenses

Share-based compensation expenses include charges related to options and restricted stock awards issued to employees, directors and non-employees. We measure share-based compensation expenses based on the grant-date fair value of any awards granted to our employees. Such expense is recognized over the requisite service period.

The following table summarizes the components of our share-based compensation expenses for the years ended December 31, 2024 and 2023 (in thousands):

Years ended December 31,

Research and development $ 51 $ 66

General and administrative 499 503

Total share-based compensation $ 550 $ 569

Our stock-based compensation expenses, which are impacted by grants of stock-based options, vesting schedule of such grants, as well as grant-date fair value of stock-based awards, remained consistent for the year ended December 31, 2024 and 2023.

Other Income (Expense)

The following table summarizes interest income, interest expense, and other income and expense for the years ended December 31, 2024 and 2023 (in thousands):

Years ended December 31,

Financing expense (3,545 ) —

Change in fair value of warrants 5,654 —

Warrant issuance costs (486 ) —

The decrease in interest expense for the year ended December 31, 2024 as compared to the same period in 2023 was primarily due to the repayment of debt principal of $1.6 million during the year ended December 31, 2023 and $4.0 million during the year ended December 31, 2024, offset by interest expenses on our line of credit facility. Interest income decreased for the year ended December 31, 2024 compared with the same period in 2023 primarily due to lower average cash and investment balances in year-to-date 2024 offset by a higher interest rate environment and accreted income on our available-for-sale securities.

We recognized approximately $3.5 million in financing expense in the consolidated statement of operations during the year ended December 31, 2024, which represents the excess of the fair value of the warrants issued in the May 2024 Private Placement (as defined below) at issuance over the proceeds. During the year ended December 31, 2024, we recognized a net fair value gain on warrant liability of $5.7 million. The warrants were amended in August 2024, as a result of which the warrants were reclassified from liability to equity on the balance sheet and are no longer required to be recorded at fair value at each period end with change in the fair value recorded in the statement of operations.

In addition, total offering expenses related to the May 2024 Private Placement of $0.4 million were recorded as a component of other expenses as the entire proceeds were allocated to the warrant liability, which could have been be settled with either our common stock or Prefunded Warrants (as defined below), which are exercisable into shares of common stock at any time at the holders’ option, but will not result in cash payment to the holders.

Liquidity and Capital Resources

The Company has funded its research and development activities through raising capital by issuing securities and receipt of research grants. As of December 31, 2024, the Company had approximately $3.6 million in combined cash and cash equivalents and short-term investments.

Short-term and long-term liquidity

The following is a summary of our key liquidity measures at December 31, 2024 and 2023 (in thousands):

As of December 31,

Cash and cash equivalents $ 76 $ 8,554

Working capital deficit $ (10,292 ) $ (893 )

We incurred net losses of $13.0 million for the year ended December 31, 2024. We have an accumulated deficit of $493.5 million as of December 31, 2024. Additionally, we used net cash of $10.6 million to fund our operating activities for the year ended December 31, 2024. These factors raise substantial doubt about our ability to continue as a going concern.

To date, our operating losses have been funded primarily from outside sources of invested capital from issuance of our common and preferred stocks, proceeds from our now-repaid in full term loan with Oxford Finance, LLC (“Oxford”), our line of credit facility with Pershing and grant funding. We have had, and will continue to have, an ongoing need to raise additional cash from outside sources to fund our future clinical development programs and other operations. There can be no assurance that we will be able to continue to raise additional capital in the future. Our inability to raise additional cash would have a material and adverse impact on our operations and ability to satisfy our obligations.

May 2024 Private Placement

In May 2024, we entered into a securities purchase agreement (the “May 2024 Purchase Agreement”), which was subsequently amended, with certain investors, including certain of the Company’s directors and executive officers (the “May 2024 Private Placement Purchasers”), whereby we issued and sold in a private placement (the “May 2024 Private Placement”): (i) 3,591,532 shares of common stock or, at the election of each investor, pre-funded warrants (“Prefunded Warrants”) to purchase shares of common stock exercisable immediately at an exercise price of $0.001 per share. Each share or Prefunded Warrant was accompanied by (i) a Series A common warrant (“May 2024 Series A Warrants”) to purchase one share of common stock, for an aggregate of 3,591,532 Series A Warrants, and (ii) one Series B common warrant (“May 2024 Series B Warrants”) to purchase one share of common stock, for an aggregate of 3,591,532 May 2024 Series B Warrants. At the closing of the May 2024 Private Placement, we received net proceeds of approximately $7.3 million.

February 2025 SPEA

On February 13, 2025 (the “SPEA Closing Date”), we entered into a securities purchase and exchange agreement (the “SPEA”) with certain existing accredited investors. Pursuant to the SPEA, on the SPEA Closing Date we issued secured convertible promissory notes (the “Funding Notes”) in the aggregate principal amount of $3,362,251 together with common stock purchase warrants (the “Warrants”) to purchase 3,002,009 shares of our common stock at an exercise price of $1.12 per share. The aggregate purchase price for the Funding Note and Warrants was approximately $3.7 million and included payment of $0.125 per Warrant in accordance with the listing rules of The Nasdaq Stock Market LLC (“Nasdaq”).

Exchange Notes

The May 2024 Purchase Agreement included certain limitations and restrictions on our ability to issue securities and provided the May 2024 Private Placement Purchasers other than our directors and executive officers (the “Outside Investors”) participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the “Financing Restrictions”). On the SPEA Closing Date, pursuant to the SPEA, the Company issued to the Outside Investors secured convertible promissory notes in the aggregate amount of $3,188,922 (the “Exchange Notes”) in exchange for cancellation of the 3,543,247 May 2024 Series A Warrants held by them, and the Outside Investors entered into a second amendment to the May 2024 Purchase Agreement to eliminate the Financing Restrictions.

As described below, we repurchased the Funding Notes and exchanged the Exchange Notes in connection with the March 2025 Private Placement.

March 2025 Private Placement

On March 4, 2025, we entered into a securities purchase agreement (the “March 2025 Purchase Agreement”) with accredited investors, including certain of our existing stockholders, identified on the signature page thereto (collectively, the “March 2025 Private Placement Purchasers”) for a private placement of securities (the “March 2025 Private Placement”) for gross proceeds of approximately $15.0 million. Pursuant to the March 2025 Purchase Agreement, we issued an aggregate of 4,069,738 shares (the “March 2025 Private Placement Shares”) of our common stock and 23,972,400 Prefunded Warrants, with each March 2025 Private Placement Share or Prefunded Warrant accompanied by (i) a Series A common warrant (the “March 2025 Series A Warrants”) to purchase one share of common stock and (ii) one Series B common warrant (the “March 2025 Series B Warrants”) to purchase one share of common stock.

The combined purchase price of $0.66 for each March 2025 Private Placement Share or $0.659 for each Prefunded Warrant in the March 2025 Private Placement, together with one accompanying March 2025 Series A Warrant and one accompanying March 2025 Series B Warrant, represented the applicable “Minimum Price” in accordance with Listing Rule 5635(d) of Nasdaq.

The initial exercise price of each March 2025 Series A Warrant is $1.32 per share of common stock. The March 2025 Series A Warrants are exercisable only following stockholder approval and expire five (5) years thereafter. The number of securities issuable under the March 2025 Series A Warrant is subject to adjustment as described in more detail in the March 2025 Series A Warrant. The March 2025 Series A Warrant exercise price and the related number of shares of common stock issuable upon exercise are subject to a “reset” provision upon certain events and are subject to anti-dilution protection upon any subsequent transaction at a fixed price lower than the warrant exercise price then in effect, as more fully described in the March 2025 Series A Warrant.

The initial exercise price of each March 2025 Series B Warrant is $1.98 per share of common stock or pursuant to an alternative cashless exercise option. The March 2025 Series B Warrants are exercisable only following stockholder approval and expire two and one-half (2.5) years thereafter. The March 2025 Series B Warrant exercise price and the related number of shares of common stock issuable upon exercise are subject to a “reset” provision upon certain events, as more fully described in the March 2025 Series B Warrant, and the March 2025 Series B Warrant alternative cashless exercise provision provides that the March 2025 Series B Warrant can be exercised without further payment to the Company and for three times the number of shares of common stock then subject to the March 2025 Series B Warrant.

Of the securities issued in the March 2025 Private Placement, 22,727,270 of the shares of common stock, or Prefunded Warrants in lieu thereof, and the accompanying 22,727,270 March 2025 Series A Warrants and 22,727,270 March 2025 Series B Warrants, were issued in consideration of new capital subscriptions, and 5,314,870 of the shares of common stock, or Prefunded Warrants in lieu thereof, and the accompanying 5,314,870 March 2025 Series A Warrants and 5,314,870 March 2025 Series B Warrants, were issued in exchange for the cancelation of the Exchange Notes.

The March 2025 Private Placement closed on March 7, 2025. The aggregate gross proceeds at the closing were approximately $15.0 million, before deducting certain expenses payable by us.

In addition to the stockholder approval of the March 2025 Series A Warrants and March 2025 Series B Warrants, we also covenanted to seek if necessary stockholder approval to, among other things, amend our Certificate of Incorporation, as amended, to increase the authorized share capital to an amount sufficient to cover the shares of common stock issuable upon the exercise of the March 2025 Series A Warrants and March 2025 Series B Warrants.

First Amendment to the February 2025 SPEA

In connection with the March 2025 Purchase Agreement, we entered into that certain First Amendment to the SPEA (the “First Amendment”). The SPEA included certain limitations and restrictions on the Company’s ability to issue securities and provided the Investors participation rights in future equity and equity-linked offerings of securities, subject to certain limited exceptions (the “New Financing Restrictions”). Pursuant to the First Amendment, subject to consummation of the March 2025 Private Placement, we agreed to repurchase from the Investors the Funding Notes and 3,002,009 warrants (the “SPEA Warrants”) issued pursuant to the SPEA for an

aggregate purchase price of $4.25 million. In exchange for the repurchase by the Company of the Funding Notes and SPEA Warrants, the Purchasers agreed to consent to the March 2025 Private Placement and eliminate the New Financing Restrictions.

CPRIT Grant

On September 19, 2022, we entered into the CPRIT Contract, pursuant to which CPRIT will provide us with the CPRIT Grant of $17.6 million subject to the terms of the CPRIT Contract, to fund approximately two-thirds of the continued development of REYOBIQTM for the treatment of patients with LM. We recognized $5.8 million, $4.9 million and $0.2 million of grant revenue during the years ended December 31, 2024, 2023 and 2022, respectively, of which $10.4 million has been received and $0.6 million was recorded as grant revenue receivable as of December 31, 2024. The amounts recognized represents CPRIT’s share of the costs incurred for our REYOBIQTM development for the treatment of patients with LM. As of December 31, 2024, we had $0.6 million of grant revenue receivable related to the CPRIT Grant. In February 2025, we received $2.0 million under the CPRIT Contract.

DoD Award

Effective September 1, 2024, we entered into an agreement with the DoD office of the Congressionally Directed Medical Research Programs to receive the DoD Award, which will be used to support the planned expansion of our clinical trial for pediatric brain cancer. On October 4, 2024, we received the first payment under the DoD Award in the amount of $0.9 million. No work under the DoD Award was commenced by December 31, 2024.

Private Equity Lines

On August 2, 2022, we entered into a purchase agreement (the “2022 Purchase Agreement”) and registration rights agreement pursuant to which Lincoln Park Capital Fund (“Lincoln Park”) committed to purchase up to $50.0 million of shares of our common stock. Under the terms and subject to the conditions of the 2022 Purchase Agreement, we have the right, but not the obligation, to sell to Lincoln Park, and Lincoln Park is obligated to purchase up to $50.0 million of shares of our common stock, provided that we cannot sell more than 57.5 million shares pursuant to the 2022 Purchase Agreement. Sales of common stock by us are subject to certain limitations, and can occur from time to time, at our sole discretion, over the 36-month period commencing on August 17, 2022, subject to the satisfaction of certain conditions. Actual sales of shares of common stock to Lincoln Park under the 2022 Purchase Agreement depend on a variety of factors to be determined by us from time to time, including, among others, market conditions, the trading price of the common stock and our determinations as to the appropriate sources of funding for the Company and its operations. As consideration for Lincoln Park’s irrevocable commitment to purchase shares of our common stock upon the terms of and subject to satisfaction of the conditions set forth in the 2022 Purchase Agreement, we paid $0.1 million in cash as an Initial Commitment Fee and issued 32,846 as the initial commitment shares to Lincoln Park in consideration for its commitment to purchase shares of our common stock at our direction under the 2022 Purchase Agreement.

On August 17, 2022, a registration statement (the “First Registration Statement”) was declared effective covering the resale of up to 633,333 shares of our common stock comprised of (i) the 32,846 initial commitment shares, and (ii) up to 600,486 shares that we have reserved for issuance and sale to Lincoln Park under the 2022 Purchase Agreement. We issued and sold 527,166 shares of common stock to Lincoln Park in connection with the First Registration Statement. An additional commitment fee equal to 2.5% of the remainder of the $50 million will be paid if and when we sell over $25.0 million of our common stock under the 2022 Purchase Agreement. The additional commitment fee may be paid in cash, common stock, or a combination thereof. We sold approximately 527,166 shares under the First Registration Statement.

On August 18, 2023, a second registration statement (the “Second Registration Statement”) was declared effective covering the resale of up to an additional 1,500,000 shares of our common stock that we reserved for issuance and sale to Lincoln Park under the 2022 Purchase Agreement from time to time. We issued and sold 150,000 shares of common stock to Lincoln Park in connection with the Second Registration Statement. We cannot sell more shares than registered under the Second Registration Statement under the 2022 Purchase Agreement without registering additional shares.

As a result of the March 2025 Private Placement, until March 4, 2026, we are unable to utilize the 2022 Purchase Agreement without the consent of investors in that offering.

During the period from August 17, 2022 to December 31, 2022, we issued 266,666 shares under the 2022 Purchase Agreement for net proceeds of approximately $3.2 million. We issued 410,500 shares under the 2022 Purchase Agreement for net proceeds of approximately $1.0 million from January 1, 2023 to December 31, 2023. No shares of common stock were purchased under the 2022 Purchase Agreement during the year ended December 31, 2024.

Nasdaq Listing Compliance

On March 8, 2024, we received notice from the Listing Qualifications staff of Nasdaq (the “Staff”), notifying us that we no longer complied with the requirement under Nasdaq Listing Rule 5550(b)(1) to maintain a minimum of $2.5 million in stockholders’ equity (the “Minimum Stockholders’ Equity Requirement”) for continued listing on The Nasdaq Capital Market or the alternative requirements of having a market value of listed securities of $35 million or net income from continuing operations of $500,000 in the most recently completed fiscal year or two of the last three most recently completed fiscal years.

On September 5, 2024, Nasdaq notified us that we had not regained compliance with Nasdaq Listing Rule 5550(b)(1). We requested a hearing before the Nasdaq Hearings Panel (the “Panel”) and on October 30, 2024, the Company received a decision from the Panel, notifying us that we had until March 4, 2025 to demonstrate compliance with the Minimum Stockholders’ Equity Requirement.

We regained compliance with the Minimum Stockholders’ Equity Requirement in connection with the March 2025 Private Placement described above.

Pursuant to Nasdaq Listing Rule 5815(d)(4)(B), we will be subject to a Mandatory Panel Monitor until March 7, 2026. If the Staff finds us again out of compliance with the Minimum Stockholders’ Equity Requirement before that date, we would not be permitted to provide the Staff with a plan of compliance with respect to that deficiency and the Staff would not be permitted to grant additional time for us to regain compliance with respect to that deficiency, nor would we be afforded an applicable cure or compliance period. Instead, the Staff would issue a “Delist Determination Letter” and we would have an opportunity to request a hearing before the Panel regarding our continued listing.

Funding and Material Cash Requirements

To date, our operating losses have been funded primarily from outside sources of invested capital from issuance of shares of our common and preferred stocks, proceeds from the now-repaid in full term loan with Oxford, the Pershing Credit Facility and grant funding. However, the Company has had, and will continue to have, an ongoing need to raise additional cash from outside sources through a combination of equity offerings, debt financings and potential collaboration, license or development agreements to fund our future clinical development programs, commercialization of CNSide, and other operations in the next twelve months from the filing of this Form 10-K. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures, or declaring dividends. There can be no assurance that we will be able to continue to raise additional capital in the future. Our inability to raise additional cash would have a material adverse impact on our operations, implementation of our strategy and ability to maintain compliance with applicable requirements, including Nasdaq listing rules.

Our present and future funding and cash requirements will depend on many factors, including, among other things:

•

the progress, timing and completion of our ongoing and planned clinical trials and nonclinical studies;

•

our ability to receive, and the timing of receipt of, future regulatory approvals for our product candidates and the costs related thereto;

•

the development and utility of the CNSideTM Test;

•

the scope, progress, results and costs of our ongoing and planned operations;

•

the costs associated with expanding our operations and building our sales and marketing capabilities;

•

our ability to establish strategic collaborations;

•

the cost and timing of preparing, filing and prosecuting patent applications, maintaining and enforcing our intellectual property rights and defending any intellectual property-related claims;

•

the revenue, if any, received from commercial sales of our product candidates, if approved; and

•

potential new product candidates that the Company identifies and attempts to develop.

The accompanying consolidated financial statements have been prepared assuming that the Company will continue to operate as a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from uncertainty related to our ability to continue as a going concern.

Cash (used in) provided by operating, investing, and financing activities for the year ended December 31, 2024 and 2023 is summarized as follows (in thousands):

Years Ended December 31,

Net cash used in operating activities $ (10,554 ) $ (12,851 )

Net cash used in investing activities (4,111 ) (160 )

Net cash provided by financing activities 6,187 3,445

Net decrease in cash and cash equivalents $ (8,478 ) $ (9,566 )

Material Cash Obligations

Under the CPRIT Contract, we receive matching funds for approximately two-thirds of the development costs for the development of REYOBIQTM for the treatment of patients with LM, subject to various funding conditions. The CPRIT Contract is effective for three years, unless otherwise terminated pursuant to the terms of the contract. CPRIT may require us to repay some or all of the disbursed CPRIT grant proceeds (with interest not to exceed 5% annually) in the event of the early termination of the CPRIT Contract.

Other than as described above, we have no purchase commitments or long-term contractual obligations, except for lease obligations as of December 31, 2024. In addition, we have no off-balance sheet arrangements (as defined in the rules and regulations of the SEC) that have or are reasonably likely to have a current or future effect on our financial condition, changes in financial condition, revenues or expenses, results of operations, liquidity, capital expenditures or capital resources that is material to investors.

Operating activities

Net cash used in operating activities for the year ended December 31, 2024 was $10.6 million compared to $12.9 million in the same period of 2023. Our operational cash use decreased by $2.3 million during the year ended December 31, 2024 as compared to the same period in 2023, due primarily to increased reimbursement under the CPRIT Contract for research and development costs related to the ReSPECT-LM program.

Investing activities

Net cash used in investing activities for the year ended December 31, 2024 was related to purchase of Biocept assets of $0.5 million, purchase of short-term investments of $15.6 million, redemption of short-term investments of $12.2 million, and purchases of fixed assets of $0.1 million. Net cash used in investing activities for the year ended December 31, 2023 was related to purchases of fixed assets of $0.1 million.

Financing Activities

Net cash provided by financing activities for the year ended December 31, 2024 was related to net proceeds of $7.3 million raised by the May 2024 Private Placement, and drawdown of $3.3 million from the Pershing Credit Facility, offset by repurchase of common stock for approximately $0.4 million and repayment of principle balance under the Oxford term loan of $4.0 million.

Net cash provided by financing activities for the year ended December 31, 2023 was primarily related to the net proceeds from sales of common stock of $5.2 million pursuant to the September 2022 Distribution Agreement with Canaccord and the 2022 Purchase Agreement with Lincoln Park, offset by $1.6 million of principal repayment under our Term Loan, and $0.1 million payment to purchase our common stock.

Critical Accounting Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”) requires us to make estimates and assumptions that affect the reported amounts of our assets, liabilities, revenue, and expenses, and that affect our recognition and disclosure of contingent assets and liabilities. On an on-going basis, we evaluate our estimates and judgments, including those related to impairment assessment of our grants and awards, indefinite lived intangible assets, and share-based compensation. We base our estimates on historical experience, known trends and events, and various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

The following listing is not intended to be a comprehensive list of all of our accounting policies. Our significant accounting policies are described in Note 2 to our financial statements contained elsewhere in this Form 10-K. In many cases, the accounting treatment of a particular transaction is dictated by U.S. GAAP, with no need for our judgment in its application. There are also areas in which our

judgment in selecting an available alternative would not produce a materially different result. We have identified the following as our critical accounting policies.

Warrant Liability

Accounting for liability classified warrants requires management to exercise judgment and make estimates and assumptions regarding their fair value. (For more information about the material inputs and assumptions used to value the liability classified warrants, refer to Note 3 to the consolidated financial statements.) The warrant liabilities are initially recorded at fair value upon the date of issuance and subsequently remeasured to fair value at each reporting date, with changes recognized in the consolidated statements of operations. Changes in the fair value of the liability classified warrants will continue to be recognized until the warrants are exercised, expire or qualify for equity classification.

In May 2024, the Company issued the May 2024 Series A Warrants and May 2024 Series B Warrants and classified them as liabilities because in certain circumstances they could have been exercised into either shares of common stock or Pre-Funded Warrants at the holder’s option and thus failed the indexation guidance under Accounting Standards Codification (“ASC”) Topic 815, Derivatives and Hedging (“ASC 815”). On August 9, 2024, the Company amended and restated the May 2024 Series A Warrants and May 2024 Series B Warrants (the “Amendment and Restatements”) to eliminate the ability of the holder to elect to receive Pre-Funded Warrants in this situation.

As a result of the Amendment and Restatements, the May 2024 Series A Warrants and May 2024 Series B Warrants, as amended, no longer fail the indexation guidance under ASC 815, and the balance of the warrant liability at the amendment date, in the amount of $5.2 million, was reclassified to equity. As a result, as of the amendment date, there was a corresponding increase in the Company's statements of stockholders’ equity.

Grants and Awards

In applying the provisions of ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”), we have determined that government grants are out of the scope of ASC 606 because the funding entities do not meet the definition of a “customer,” as defined by ASC 606, as we do not consider there to be a transfer of control of goods or services. With respect to the grant, we evaluate if it has a collaboration in accordance with ASC Topic 808, Collaborative Arrangements (“ASC 808”). For grants outside the scope of ASC 808, we apply International Accounting Standards No. 20 (“IAS 20”), Accounting for Government Grants and Disclosure of Government Assistance, by analogy, and revenue is recognized when we incur expenses related to the grant for the amount we are entitled to under the provisions of the contract.

We also consider the guidance in ASC Topic 730, Research and Development, which requires an assessment, at the inception of the grant, of whether the agreement is a liability. If we are obligated to repay funds received regardless of the outcome of the related research and development activities, then we are required to estimate and recognize that liability. Alternatively, if we are not required to repay the funds, then payments received are recorded as revenue or contra-expense as the expenses are incurred. Deferred grant liability represents grant funds received or receivable for which the allowable expenses have not yet been incurred as of the balance sheet date. Grant Receivable represents grant funds not yet received for which the allowable expenses have been incurred as of the balance sheet date.

Impairment of Goodwill

We perform our goodwill impairment analysis at the reporting unit level. For the years ended December 31, 2024 and 2023, our company has one reporting unit. We perform our annual impairment analysis by either doing a qualitative assessment of a reporting unit’s fair value from the last quantitative assessment to determine if there is potential impairment, or comparing a reporting unit’s estimated fair value to its carrying amount. If a quantitative assessment is performed the evaluation includes management estimates of cash flow projections based on internal future projections and/or use of a market approach by looking at market values of comparable companies. Our market capitalization is also considered as a part of this analysis.

In accordance with our accounting policy, we completed the annual evaluation for impairment of goodwill as of December 31, 2024 using the qualitative method and determined that no impairment existed.

Share-based Compensation

Compensation expense related to stock options granted is measured at the grant date based on the estimated fair value of the award and is recognized on an accelerated attribution method over the requisite service period. We determine the estimated fair value of each stock option on the date of grant using the Black-Scholes valuation model which uses assumptions regarding a number of complex and subjective variables. The risk-free interest rate is based on the U.S. Treasury yield for a period consistent with the expected term of the option in effect at the time of the grant. Expected volatility is based on an analysis of the historical volatility of our common stock. The expected term represents the period that we expect our stock options to be outstanding. The expected term assumption is estimated using the simplified method set forth in the SEC's Staff Accounting Bulletin 110, which is the mid-point between the option vesting date and the expiration date. We have never declared or paid dividends on our common stock and have no plans to do so in the foreseeable future.

Changes in these assumptions may lead to variability with respect to the amount of stock compensation expense we recognize related to stock options.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Not applicable.

Item 8. Financial Statements and Supplementary Data

Page

Consolidated Balance Sheets as of December 31, 2024 and 2023 77

Notes to Financial Statements 81

Report of Independent Registered Public Accounting Firm

Shareholders and Board of Directors

Plus Therapeutics, Inc.

Houston, Texas

Opinion on the Consolidated Financial Statements

We have audited the accompanying consolidated balance sheets of Plus Therapeutics, Inc. (the “Company”) as of December 31, 2024 and 2023, the related consolidated statements of operations, stockholders’ equity (deficit), and cash flows for each of the years then ended and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2024 and 2023, and the results of its operations and its cash flows for each of the years then ended, in conformity with accounting principles generally accepted in the United States of America.

Going Concern Uncertainty

The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 1 to the consolidated financial statements, the Company has suffered recurring losses and negative cash flows from operations that raise substantial doubt about its ability to continue as a going concern. Management’s plans in regard to these matters are also described in Note 1. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s consolidated financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (“PCAOB”) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the consolidated financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Determination of Research and Development Cost Associated With Recording of Grant Revenue

As described in Note 11 to the consolidated financial statements, in September 2022, the Company entered into a contract with the Cancer Prevention and Research Institute of Texas (“CPRIT”) pursuant to which CPRIT will provide the Company a grant of up to $17.6 million (the “CPRIT Grant”) over a three-year period. The CPRIT Grant is subject to customary CPRIT funding conditions, including, but not limited to, fund the continued development of rhenium (186Re) obisbemeda for the treatment of patients with leptomeningeal metastases (“LM”).” The Company recognized $5.8 million in grant revenue from the CPRIT Grant during the year ended December 31, 2024.

We identified the determination of research and development costs incurred associated with the CPRIT Grant as a critical audit matter because of the subjectivity required to appropriately determine whether such costs satisfied the funding conditions. Auditing this element involved especially challenging and subjective auditor judgment due to the nature and extent of auditor effort required to address the matter.

The primary procedures we performed to address this critical audit matter included:

•

Reviewing the CPRIT Grant agreement to understand the conditions for which research and development costs satisfy the funding conditions.

•

Reviewing evidence of CPRIT’s approval of costs submitted by the Company that were applied to the CPRIT Grant funding conditions.

•

Inspecting a sample of vendor agreements and invoice detail to determine whether certain charges satisfy the CPRIT Grant funding conditions.

We have served as the Company’s auditor since 2016.

/s/ BDO USA P.C.

Austin, Texas

March 31, 2025

PLUS THERAPEUTICS, INC.

CONSOLIDATED BALANCE SHEETS

(in thousands, except share and par value data)

As of December 31,

Assets

Current assets:

Cash and cash equivalents $ 76 $ 8,554

Grant receivable 571 —

Property and equipment, net 448 906

Operating lease right-of-use assets 73 202

Intangible assets, net 469 42

Liabilities and Stockholders’ Equity (Deficit)

Current liabilities:

Accounts payable and accrued expenses $ 11,288 $ 6,631

Operating lease liability 44 120

Deferred grant liability 927 —

Line of credit 3,292 —

Term loan obligation, current — 3,976

Noncurrent operating lease liability 31 85

Deferred grant liability — 1,924

Commitments and contingencies (Note 7)

Stockholders’ equity (deficit):

Total stockholders’ equity (deficit) (8,949 ) (1,348 )

Total liabilities and stockholders’ equity (deficit) $ 6,633 $ 11,388

See Accompanying Notes to these Consolidated Financial Statements

PLUS THERAPEUTICS, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(in thousands, except share and per share data)

For the Years Ended December 31,

Operating expenses:

Other income (expense):

Financing expense (3,545 ) —

Change in fair value of warrants 5,654 —

Warrant issuance costs (486 ) —

Total other income 1,717 5

Per share information:

Net loss per share of common stock - basic $ (1.95 ) $ (4.24 )

Net loss per share of common stock - diluted $ (2.34 ) $ (4.24 )

See Accompanying Notes to these Consolidated Financial Statements

PLUS THERAPEUTICS, INC.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT)

(in thousands, except share data)

Convertible Additional Total

Preferred Stock preferred stock Common stock paid-in Accumulated stockholders’

Issuance of Series F preferred stock 1 — — — — — — — — — —

Redemption of Series F preferred stock (1 ) — — — — — — — — — —

Share-based compensation — — — — — — — — 569 — 569

Fractional adjustment — — — — (1,310 ) — — — — — —

Purchase of treasury stock — — — — — — (78,559 ) (126 ) — — (126 )

Issuance of common stock — — — — 1,439,988 1 — — — — 1

Exercise of pre-funded warrants — — — — 192,114 — — — — — —

Purchase of treasury stock — — — — — — (179,866 ) (374 ) — — (374 )

Share-based compensation — — — — — — — — 550 — 550

Reclass of warrants to equity — — — — — — — — 5,200 — 5,200

See Accompanying Notes to these Consolidated Financial Statements

PLUS THERAPEUTICS, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(in thousands)

For the Years Ended December 31,

Cash flows used in operating activities:

Adjustments to reconcile net loss to net cash used in operating activities:

Depreciation and amortization 723 628

Amortization of deferred financing costs and debt discount 20 190

Common stock issued for research and development — 75

Accretion of discount on short-term investments (111 ) —

Non-cash financing expenses 3,545 —

Change in fair value of warrants (5,654 ) —

Loss on disposal of property and equipment — 2

Share-based compensation expense 550 569

Reduction in the carrying amount of operating lease right-of-use assets 129 117

Grant receivable (571 ) —

Accounts payable and accrued expenses 4,702 (3,677 )

Change in operating lease liabilities (130 ) (117 )

Deferred grant liability (997 ) 281

Net cash used in operating activities (10,554 ) (12,851 )

Cash flows used in investing activities:

Purchases of property and equipment (146 ) (160 )

Purchases of intangible assets (545 ) —

Purchases of short-term investments (15,590 ) —

Redemption of short-term investments 12,170 —

Net cash used in investing activities (4,111 ) (160 )

Cash flows from financing activities:

Principal payments of long-term obligations (3,996 ) (1,608 )

Proceeds from credit facility 3,292 —

Payment of offering costs related to sale of common stock — (348 )

Purchase of treasury stock (374 ) (126 )

Net cash provided by financing activities 6,187 3,445

Net decrease in cash and cash equivalents (8,478 ) (9,566 )

Cash and cash equivalents at beginning of period 8,554 18,120

Cash and cash equivalents at end of period $ 76 $ 8,554

Supplemental disclosure of cash flows information:

Cash paid during period for:

Supplemental schedule of non-cash investing and financing activities:

Unpaid offering cost $ — $ 174

Common stock issued in payment for in process research and development $ — $ 75

Right-of-use assets acquired by assuming operating lease liabilities $ — $ 71

See Accompanying Notes to these Consolidated Financial Statements

PLUS THERAPEUTICS, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

December 31, 2024

Organization and Operations

The Company

Plus Therapeutics, Inc. is a clinical-stage pharmaceutical company focused on the development, manufacture and commercialization of complex and innovative treatments for patients battling cancer and other life-threatening diseases. CNSide Diagnostics, LLC is a wholly owned subsidiary of Plus Therapeutics, Inc. that develops and commercializes proprietary laboratory-developed tests, such as the CNSideTM Test, designed to identify tumor cells that have metastasized to the central nervous system in patients with carcinomas and melanomas.

Certain Risks and Uncertainties

The Company’s prospects are subject to the risks and uncertainties frequently encountered by companies in the early stages of development and commercialization, especially those companies in rapidly evolving and technologically advanced industries such as the biotech/medical device field. The Company’s future viability largely depends on its ability to complete development of new products and receive regulatory approvals for those products. No assurance can be given that the Company’s new products will be successfully developed, regulatory approvals will be granted, or acceptance of these products will be achieved.

Going Concern

The Company incurred net losses of $13.0 million for the year ended December 31, 2024, and as of December 31, 2024, the Company had an accumulated deficit of $493.5 million and cash and cash equivalents of $76,000 and short term investments of $3.5 million. Additionally, the Company used net cash of $10.6 million to fund its operating activities for the year ended December 31, 2024. The Company had an outstanding balance of $3.3 million under its line of credit facility (Note 9). The Company expects that its research and development expenditures will increase in absolute dollars in 2025 and beyond. These factors raise substantial doubt about the Company’s ability to continue as a going concern.

As disclosed in more detail in Note 15 and Note 18, the Company has entered into various financing agreements and raised capital by issuing its common stock.

Nasdaq Listing Compliance

On March 8, 2024, the Company received a written notice (the “Notice”) from the Listing Qualifications staff of Nasdaq, notifying the Company that it no longer complied with the requirement under Nasdaq Listing Rule 5550(b)(1) to maintain a minimum of $2.5 million in stockholders’ equity (the “Minimum Stockholders’ Equity Requirement”) for continued listing on The Nasdaq Capital Market or the alternative requirements of having a market value of listed securities of $35 million or net income from continuing operations of $500,000 in the most recently completed fiscal year or two of the last three most recently completed fiscal years.

On September 5, 2024, Nasdaq notified the Company that it had not regained compliance with Nasdaq Listing Rule 5550(b)(1). The Company requested a hearing before the Nasdaq hearing panel (“Panel”), and on October 30, 2024, the Company received a decision from the Panel, notifying the Company that it had until March 4, 2025, to demonstrate compliance with the Minimum Stockholders’ Equity Requirement.

The Company regained compliance with the Minimum Stockholders’ Equity Requirement in connection with the private placement entered into on March 4, 2025, as described in more detail in Note 18, Subsequent Events.

Pursuant to Nasdaq Listing Rule 5815(d)(4)(B), the Company will be subject to a Mandatory Panel Monitor until March 7, 2026. If the Nasdaq Listing Qualifications staff (the “Staff”) finds the Company again out of compliance with the Minimum Stockholders’ Equity Requirement before that date, the Company would not be permitted to provide the Staff with a plan of compliance with respect to that deficiency and the Staff would not be permitted to grant additional time for the Company to regain compliance with respect to that deficiency, nor would the Company be afforded an applicable cure or compliance period. Instead, the Staff would issue a “Delist Determination Letter” and the Company would have an opportunity to request a Nasdaq hearing panel regarding its continued listing.

The Company continues to seek additional capital through strategic transactions and from other financing alternatives. Without additional capital, current working capital and cash generated from sales will not provide adequate funding to make debt repayments, for research, sales and marketing efforts and product development activities at their current levels. If sufficient capital

is not raised, the Company will at a minimum need to significantly reduce or curtail its research and development and other operations, and this would negatively affect its ability to achieve corporate growth goals.

Should the Company fail to raise additional cash from outside sources, this would have a material adverse impact on its operations.

The accompanying financial statements have been prepared assuming the Company will continue to operate as a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from uncertainty related to its ability to continue as a going concern.

Summary of Significant Accounting Policies

Use of Estimates

The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions affecting the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting period. The most significant estimates and critical accounting policies involve reviewing assets for impairment, and determining the assumptions used in measuring share-based compensation expense and warrant liability.

Actual results could differ from these estimates. Management’s estimates and assumptions are reviewed regularly, and the effects of revisions are reflected in the financial statements in the periods they are determined to be necessary.

Cash and cash equivalents

The Company considers all highly liquid investments with maturities of three months or less at the time of purchase to be cash equivalents.

Cash and cash equivalents include cash in readily available checking, savings accounts and money market accounts. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash balances due to the financial position of the depository institution in which those deposits are held.

Financial Instruments

Financial instruments include cash equivalents, other current assets, accounts payable, accrued expenses, other liabilities and long-term debt. The carrying values of cash equivalents, other current assets, accounts payable, accrued expenses and other liabilities generally approximate fair value due to the short-term nature of these instruments. Based on level 3 inputs and the borrowing rates currently available for loans with similar terms, the Company believes the fair value of the long-term debt is materially consistent with its carrying value.

Property and Equipment

Property and equipment are stated at cost, net of accumulated depreciation. Depreciation expense, which includes the amortization of capitalized leasehold improvements, is provided for on a straight-line basis over the estimated useful lives of the assets, or the life of the lease, whichever is shorter, and range from three to five years. When assets are sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and the resulting gain or loss, if any, is included in operations. Maintenance and repairs are charged to operations as incurred.

Impairment

The Company assesses its property and equipment and intangible assets for potential impairment when there is a change in circumstances that indicates carrying values of assets may not be recoverable. Such long-lived assets are deemed to be impaired when the undiscounted cash flows expected to be generated by the asset (or asset group) are less than the asset’s carrying amount. Any required impairment loss would be measured as the amount by which the asset’s carrying value exceeds its fair value and would be recorded as a reduction in the carrying value of the related asset and a charge to operating expense. The Company recognized no impairment losses during any of the periods presented in these financial statements.

Goodwill

The Company’s goodwill represents the excess of the cost over the fair value of net assets acquired from its business combinations. The determination of the value of goodwill arising from business combinations requires extensive use of accounting estimates and judgments to allocate the purchase price to the fair value of the net tangible and intangible assets acquired.

Goodwill is not amortized; however, it is assessed for impairment using fair value measurement techniques on an annual basis or more frequently if facts and circumstance warrant such a review. Goodwill is considered to be impaired if the Company determines that the carrying value of the reporting unit exceeds its fair value.

The Company performs its impairment test annually during the fourth quarter by comparing the Company’s estimated fair value, calculated from the Company’s market capitalization, to its carrying amount. The Company’s annual evaluation for impairment of goodwill consists of one reporting unit. The Company completed its most recent annual evaluation for impairment as of December 31, 2024, when the Company had stockholders' deficit within its sole reporting unit of approximately $8.9 million, and concluded that no impairment existed.

Grant Revenue Recognition

In applying the provisions of Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“ASC 606”), the Company has determined that government grants are out of the scope of ASC 606 because the funding entities do not meet the definition of a “customer,” as defined by ASC 606, as there is not considered to be a transfer of control of goods or services. With respect to the grant, the Company determines if it is a collaboration arrangement in accordance with ASC Topic 808, Collaborative Arrangements (“ASC 808”). For grants outside the scope of ASC 808, the Company applies International Accounting Standards No. 20, Accounting for Government Grants and Disclosure of Government Assistance, by analogy, and revenue is recognized when the Company incurs expenses related to the grant for the amount the Company is entitled to under the provisions of the contract.

The Company also considers the guidance in ASC Topic 730, Research and Development (“ASC 730”), which requires an assessment, at the inception of the grant, of whether the agreement is a liability. If the Company is obligated to repay funds received regardless of the outcome of the related research and development activities, then the Company is required to estimate and recognize that liability. Alternatively, if the Company is not required to repay the funds, then payments received are recorded as revenue or contra-expense as the expenses are incurred.

Deferred grant liability represents grant funds received or receivable for which the allowable expenses have not yet been incurred as of the balance sheet date. Grant Receivable represents grant funds not yet received for which the allowable expenses have been incurred as of the balance sheet date.

Research and Development

Research and development expenditures, which are charged to operations in the period incurred, include costs associated with the design, development, testing and enhancement of the Company’s products, regulatory fees, the purchase of laboratory supplies, and pre-clinical and clinical studies as well as salaries and benefits for the Company's research and development employees.

Warrants

Warrants are accounted for as either derivative liabilities or as equity instruments depending on the specific terms of the agreement in accordance with applicable accounting guidance provided in ASC Topic 815 - Derivatives and Hedging. Equity-classified instruments are recorded in additional paid-in capital at issuance and are not subject to remeasurement. Liability-classified warrants are recorded at fair value at each reporting period with any change in fair value recognized as a component of change in fair value of warrants in the consolidated statements of operations. The Company periodically evaluates changes in facts and circumstances that could impact the classification of warrants.

Available-for-Sale Securities

The Company’s available-for-sale securities consist of U.S. government and agency securities. Securities with maturities from the date of purchase of less than three months are included in cash equivalents. The Company classifies its marketable securities as available-for-sale and records such assets at estimated fair value in the consolidated balance sheets, with unrealized gains and losses, if any, reported as a component of other comprehensive income (loss) within the consolidated statements of operations and comprehensive income/loss and as a separate component of stockholders’ equity. Realized gains and losses are calculated on the specific identification method and recorded as interest income (loss). At each balance sheet date, the Company assesses available-for-sale securities in an unrealized loss position to determine whether the decline in fair value below amortized cost is a result of credit losses or other factors, whether the Company expects to recover the amortized cost of the security, the Company’s intent to sell and if it is more likely than not that the Company will be required to sell the securities before the recovery of amortized cost.

The Company records changes in allowance for expected credit loss in other income (expense). There has been no allowance for expected credit losses recorded during any of the periods presented.

Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Accretion of discounts are recorded in interest income in the consolidated statements of operations and comprehensive income/loss.

During the year ended December 31, 2024, the total unrealized gains and losses on the Company’s available-for-sale securities were immaterial, and not presented separately in the consolidated statement of operations.

Deferred Financing Costs and Other Debt-Related Costs

Deferred financing costs are capitalized, recorded as an offset to debt balances and amortized to interest expense over the term of the associated debt instrument using the effective interest method. If the maturity of the debt is accelerated because of default or early debt repayment, then the amortization would be accelerated.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income (loss) in the years in which those temporary differences are expected to be recovered or settled. Due to our history of losses, a full valuation allowance has been recognized against our deferred tax assets.

The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. For the years ended December 31, 2024 and 2023, the Company has not recorded any interest or penalties related to income tax matters. The Company does not foresee any material changes to unrecognized tax benefits within the next twelve months.

Share-Based Compensation

The Company recognizes the fair value of all share-based payment awards in our statements of operations over the requisite vesting period of each award, which approximates the period during which the employee and non-employee director is required to provide service in exchange for the award. The Company estimates the fair value of these options using the Black-Scholes option pricing model using assumptions for expected volatility, expected term, and risk-free interest rate. Expected volatility is based primarily on historical volatility and is computed using daily pricing observations for recent periods that correspond to the expected term of the options. The expected term represents the period of time that options are expected to be outstanding. Because the Company does not have historical exercise behavior, it determines the expected life assumption using the simplified method which is an average of the contractual term of the option and its vesting period. The risk-free interest rate is the interest rate for treasury instruments with maturities that approximate the expected term.

Segment Information

For the years ended December 31, 2024 and 2023, the Company is managed as a single operating segment, and therefore reports its results in one operating segment.

Loss Per Share

Basic per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period. Diluted per share data is computed by dividing net income or loss applicable to common stockholders by the weighted average number of common shares outstanding during the period increased to include, if dilutive, the number of additional common shares that would have been outstanding as calculated using the treasury stock method. Potential common shares were related entirely to outstanding but unexercised options, warrants and convertible preferred stocks for all periods presented.

Concentration Risk

Although the Company’s contracts with its vendors are not exclusive, the Company currently uses sole source providers for core materials used in its clinical trials.

Recently Issued Accounting Pronouncements

In November 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The new standard is intended to improve annual and interim reportable segment disclosure requirements regardless of number of reporting units,

primarily through enhanced disclosures of significant expenses. The amendment requires public entities to disclose significant segment expenses that are regularly provided to the Company's chief operating decision maker (“CODM”) and included within each reported measure of segment profit and loss. This update is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years starting after December 15, 2024. This ASU must be applied retrospectively to all prior periods presented. Management adopted this ASU as of December 31, 2024 and included additional disclosures as required in the footnotes to this annual report on Form 10-K.

In December 2023, the FASB issued ASU No. 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosure. This ASU includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The ASU is effective for years beginning after December 15, 2024, but early adoption is permitted. This ASU should be applied on a prospective basis, although retrospective application is permitted. Management does not expect the adoption of this ASU to have a material impact on the Company’s consolidated financial statements and related disclosures.

In November 2024, the FASB issued ASU 2024-03 Income Statement (Topic 220): Reporting Comprehensive Income - Expense Disaggregation Disclosures, which requires an entity to disclose on an annual and interim basis, disaggregated information about specific income statement expense categories. The guidance should be applied prospectively with the option to apply the standard retrospectively. The standard becomes effective for the annual period starting on January 1, 2027 and interim periods starting on January 1, 2028. The Company is in the process of analyzing the impact that the adoption of ASU 2024-03 will have on its disclosures.

Fair Value Measurements

Fair value measurements are market-based measurements, not entity-specific measurements. Therefore, fair value measurements are determined based on the assumptions that market participants would use in pricing the asset or liability. The Company follows a three-level hierarchy to prioritize the inputs used in the valuation techniques to derive fair values. The basis for fair value measurements for each level within the hierarchy is described below:

•

Level 1: Quoted prices in active markets for identical assets or liabilities.

•

Level 2: Quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs are observable in active markets.

•

Level 3: Valuations derived from valuation techniques in which one or more significant inputs are unobservable in active markets.

The Company has investments in money market accounts, which are included in cash and cash equivalents on the balance sheets. Fair value inputs for these investments are considered Level 1 measurements within the fair value hierarchy since money market account fair values are known and observable through daily published floating net asset values.

The following table summarizes the Company’s fair value hierarchy for its financial assets measured at fair value on a recurring basis as of December 31, 2024 and December 31, 2023, respectively (in thousands).

Fair Value Measurements Using

December 31, 2024 Fair Value Level 1 Level 2 Level 3

Cash equivalents

Money market $ 74 $ 74 $ — $ —

Total cash equivalents $ 74 $ 74 $ — $ —

Investments

Government agency bonds 772 772 — —

Fair Value Measurements Using

December 31, 2023 Fair Value Level 1 Level 2 Level 3

During the year ended December 31, 2024, the Company issued common stock warrants which were initially classified as liabilities under authoritative accounting standards, and reclassified in the equity section of the balance sheet upon modification

in August 2024 (See Note 15, Stockholders’ Deficit - May 2024 Private Placement, for further details). These common stock warrants were valued using the Black Scholes model, with level 3 inputs such as expected volatility, risk-free interest rate, and expected term that are not observable in active markets.

The table below summarizes key inputs used in the valuation of the liability classified warrants as of the issuance date and as of the date of amendment:

As of issuance date As of date of amendment

Expected term 1.1 - 5.0 years 0.9 - 4.7 years

The table below provides a summary of the fair value of the Company’s warrant liability during year ended December 31, 2024 (in thousands). As of December 31, 2023, the fair value of liability classified warrants was immaterial, and the change in the fair value of liability classified warrants during the year ended December 31, 2023 was immaterial.

Twelve Months Ended December 31, 2024

Warrant liability

Beginning balance $ —

Issuance of warrants 10,854

Change in fair value of warrants (5,654 )

Reclassification to equity (5,200 )

Ending balance $ —

Nonfinancial Assets and Liabilities

The Company applies fair value techniques on a non-recurring basis, if and when necessary, associated with: (1) valuing potential impairment losses related to goodwill and intangible assets which are accounted for pursuant to the authoritative guidance for intangibles—goodwill and other; and (2) valuing potential impairment losses related to long-lived assets which are accounted for pursuant to the authoritative guidance for property, plant and equipment. There was no impairment related to long lived assets, intangible assets, or goodwill during the years ended December 31, 2024 or 2023.

4. Investments

As of December 31, 2024, the Company had total investments of $3.5 million of money market accounts, treasury bills, and government agency bonds, with total amortized cost and fair value of $3.5 million. These investments are collateralized marketable securities as described in footnote 10. The Company did not have investments as of December 31, 2023.

As of December 31, 2024, the Company classified available-for-sales as short-term investments in the consolidated balance sheet because the maturity dates were less than one year from the date of the purchase.

5. Loss per Share

The shares of the Company's common stock underlying the pre-funded warrants described in Note 15, are included in the weighted average outstanding common stock in the calculation of basic and diluted net loss per share. The Company considers Series A Warrants, and Series B Warrants to be participating securities, because holders of such instruments participate in the event a dividend is paid on common stock. The holders of the Series A Warrants and Series B Warrants do not have a contractual obligation to share in the Company’s losses. As such, losses are attributed entirely to common stockholders.

The following table sets forth the computation of basic and diluted net loss per share of common stock for the periods indicated, in thousands except share and per share data:

For the Year Ended December 31,

Basic and diluted net loss per share of common stock calculation:

Change in fair value of warrants (5,047 ) -

Net loss attributable to common stockholders - diluted $ (18,025 ) $ (13,316 )

Weighted average shares of common stock outstanding - basic 6,640,251 3,140,925

Net loss per share of common stock - basic $ (1.95 ) $ (4.24 )

Net loss per share of common stock - diluted $ (2.34 ) $ (4.24 )

The following were excluded from the diluted loss per share calculation for the periods presented because their effect would be anti-dilutive:

For the Year Ended December 31,

6. Composition of Certain Financial Statement Captions

Other Current Assets

As of December 31, 2024 and 2023, other current assets were comprised of the following (in thousands):

December 31,

Prepaid services $ 87 $ 410

Property and Equipment, net

As of December 31, 2024 and 2023, property and equipment, net, were comprised of the following (in thousands):

December 31,

Office and computer equipment $ 1,778 $ 1,632

Less accumulated depreciation (3,140 ) (2,536 )

Depreciation expense totaled $0.6 million for each of the years ended December 31, 2024 and 2023, respectively.

Intangible Assets, net

As of December 31, 2024, intangible assets included the net book value of costs incurred for purchase of Biocept intellectual properties (Note 12) and software upgrades. Amortization expenses totaled $0.1 million for each of the years ended December 31, 2024 and 2023.

As of December 31, 2024 intangible assets, net, were comprised of the following (in thousands):

Gross Carrying Amount Accumulated Amortization Intangible Asset, Net

As of December 31, 2023 intangible assets, net, were comprised of the following (in thousands):

Gross Carrying Amount Accumulated Amortization Intangible Asset, Net

Total intangible assets $ 221 $ (179 ) $ 42

As of December 31, 2024, future amortization expense on intangible assets is estimated to be as follows (in thousands):

Year Ending December 31, Amount

Total future amortization expense $ 469

Accounts Payable and Accrued Expenses

As of December 31, 2024 and 2023, accounts payable and accrued expenses were comprised of the following (in thousands):

December 31,

Accrued payroll and bonus 920 987

Accrued professional fees 236 128

Accrued vacation and compensation 356 370

Accrued interest 117 —

7. Commitments and Contingencies

Leases

At the inception of a contractual arrangement, the Company determines whether the contract contains a lease by assessing whether there is an identified asset and whether the contract conveys the right to control the use of the identified asset in exchange for consideration over a period of time. If both criteria are met, the Company calculates the associated lease liability and corresponding right-of-use asset upon lease commencement using a discount rate based on the rate implicit in the lease or an incremental borrowing rate commensurate with the term of the lease. Lease renewable options are included in the estimation of lease term when it is reasonably certain that the Company will exercise such options.

The Company records lease liabilities within current liabilities or long-term liabilities based upon the length of time associated with the lease payments. The Company records its operating lease right-of-use assets as long-term assets. Leases with an initial

term of 12 months or less are not recorded on the balance sheets. Instead, the Company recognizes lease expense for these leases on a straight-line basis over the lease term in the statements of operations.

The Company leased laboratory, office and storage facilities in San Antonio, Texas, under operating lease agreements that expire in 2025. The Company also leased, through December 31, 2024, certain office space in Austin, Texas under a month-to-month operating lease agreement and certain office space in Charlottesville, Virginia (the “Charlottesville Lease”). The Company’s existing operating lease agreements generally provide for periodic rent increases, and renewal and termination options. The Company’s lease agreements do not contain any material variable lease payments, residual value guarantees or material restrictive covenants.

The Charlottesville Lease has a term of 12 months and the Company has the ability to renew for three additional one-year periods. On March 31, 2023, Company believed that it was reasonably certain that the Charlottesville Lease will be renewed through March 31, 2026, and as a result, it remeasured the related lease liability as of March 31, 2023 to be $80,000 using the then-in-effect discount rate of 12.76%. Effective July 1, 2023, the Company added additional office lease premises in Charlottesville, which was accounted for as a separate operating lease contract with a lease liability and corresponding right-of-use asset of $19,000, at a discount rate of 13.47%.

Certain leases require the Company to pay taxes, insurance, and maintenance. Payments for the transfer of goods or services such as common area maintenance and utilities represent non-lease components. The Company elected the package of practical expedients and therefore does not separate non-lease components from lease components.

The Company’s operating lease liabilities and corresponding right-of-use assets are included in the balance sheets. As of December 31, 2024, the weighted average discount rate used to measure operating lease liabilities and the operating leases remaining term were 11.6% and 0.9 years, respectively.

The table below summarizes the Company’s operating lease costs from its statements of operations, and cash payments from its statements of cash flows (in thousands).

Year Ended December 31,

Lease expense:

Operating lease expense $ 145 $ 141

Total lease expense $ 145 $ 141

Cash payment information:

Operating cash used for operating leases $ 180 $ 141

Total rent expenses for each of the years ended December 31, 2024 and 2023 was $0.2 million, which includes leases in the table above, month-to-month operating leases, and common area maintenance charges.

The Company’s future minimum annual lease payments under operating leases at December 31, 2024 are as follows (in thousands):

Operating Leases

Total minimum lease payments 80

Less: amount representing interest $ (5 )

Present value of obligations under leases 75

Less: current portion 44

Noncurrent lease obligations $ 31

Manufacturing Agreement with SpectronRX

On November 5, 2024, the Company entered into a manufacturing services agreement with SpectronRx for drug product development and manufacturing, which includes an initial commitment fee of $0.3 million. Under this agreement, the Company will own all rights to intellectual property related to the products developed, while SpectronRx retains rights to its own technology.

SpectronRx is required to negotiate a commercial supply agreement upon six months' written notice before the Company's first commercial manufacturing needs. The agreement will remain in place for five years, automatically renewing for successive one-year terms unless terminated with six months' notice. During the year ended December 31, 2024, the Company did not recognize any expenses related to this agreement.

Other Commitments and Contingencies

The Company has entered into agreements with various research organizations for pre-clinical and clinical development studies, which have provisions for cancellation. Under the terms of these agreements, the vendors provide a variety of services including conducting research, recruiting and enrolling patients, monitoring studies and data analysis. Payments under these agreements typically include fees for services and reimbursement of expenses. The timing of payments due under these agreements is estimated based on current study progress. As of December 31, 2024, the Company did not have any clinical research study obligations.

The Company has entered into service and subscription-based agreements, which are recorded in accounts payable and accrued expenses, with an offsetting amount included in deferred costs within other current assets (see Note 6).

Legal proceedings

The Company is subject to various claims and contingencies related to legal proceedings. Due to their nature, such legal proceedings involve inherent uncertainties including, but not limited to, court rulings, negotiations between affected parties and governmental actions. Management assesses the probability of loss for such contingencies and accrues a liability and/or discloses the relevant circumstances, as appropriate.

8.License Agreements

UT Health Science Center at San Antonio (“UTHSCSA”) License Agreement

On December 31, 2021, the Company entered into a Patent and Know-How License Agreement with UTHSCSA, pursuant to which UTHSCSA granted the Company an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense and to make, develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of biodegradable alginate microspheres containing nanoliposomes loaded with imaging and/or therapeutic payloads.

NanoTx License Agreement

On March 29, 2020, the Company and NanoTx, Corp. (“NanoTx”) entered into a Patent and Know-How License Agreement (the “NanoTx License Agreement”), pursuant to which NanoTx granted the Company an irrevocable, perpetual, exclusive, fully paid-up license, with the right to sublicense and to make, develop, commercialize and otherwise exploit certain patents, know-how and technology related to the development of radiolabeled nanoliposomes.

The transaction terms included an upfront payment of $0.4 million in cash and $0.3 million in the Company's voting stock. The transaction terms also included success-based milestone and royalty payments contingent on key clinical, regulatory and sales milestones, as well as the requirement to pay 15% of any non-dilutive monetary awards or grants received from external agencies to support product development of the nanoliposome encapsulated BMEDA-chelated radioisotope, which includes grants from the Cancer Prevention & Research Institute of Texas ("CPRIT"). As of December 31, 2024, the Company accrued $1.0 million of payments due to NanoTx as a result of the CPRIT grant received (Note 11).

9. Term Loan Obligations

On May 29, 2015, the Company entered into the Loan and Security Agreement (the “Loan and Security Agreement”), pursuant to which Oxford Finance, LLC (“Oxford”) funded an aggregate principal amount of $17.7 million (the “Term Loan”), subject to the terms and conditions set forth in the Loan and Security Agreement.

Pursuant to the Loan and Security Agreement, as amended, the Company made interest only payments through May 1, 2021, and thereafter was required to make payments of principal and accrued interest in equal monthly installments sufficient to amortize the Term Loan through June 1, 2024, the maturity date. On June 3, 2024, the Company paid off the Term Loan by making a final payment in an aggregate amount equal to approximately $3.3 million, which included both the balance of outstanding principal and interest and the final payment fee due. The repayment in full of the Term Loan terminated Oxford’s security interest in the Company’s existing and after-acquired assets, as well as all other restrictions and covenants under the Term Loan.

10. Line of Credit Facility

PSTV US Equity

PSTV · 10-K · period ended 2024-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

PSTV US Equity☆

PSTV · 10-K · period ended 2024-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

PSTV US Equity